Promoter Eddie Hearn has said returning to the US - where 29-year-old Joshua fell to a shock defeat at New York's Madison Square Garden - is unlikely.

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A potential stumbling block for Saudi Arabia could be the country's time zone, which is three hours ahead of GMT. Joshua's bouts are televised on Sky Sports Box Office in the UK and the DAZN streaming service in the US.

If the bout started at midnight in the Middle East in December it would be taking place in early afternoon in Los Angeles and early evening in New York - times which could prove unpopular with fans paying to stream what will be the biggest fight in the sport this year.

Saudi Arabia has made plays to hold significant sporting events in recent years, and hosted British boxer Amir Khan's recent win over Billy Dib and Callum Smith's success over George Groves in the World Boxing Super Series final in September.

Ruiz scored four knockdowns on his way to a seventh-round stoppage on what was Joshua's much-publicised US debut on 1 June. The result ranked as one of the biggest upsets in the history of the heavyweight division, with Joshua a 1-25 favourite before the bout.